Increase 120 centimetres by 24%

It is a simple problem where 120 centimeters need to be increased by 24%. The increased length can be found by:
120 * (24/100)
= 12 * (24/10)
= 288/10
= 28.8 centimeters
Then the total length of increase = 28.8 cm
Then the increased length = (120 + 28.8) cm
                                         = 148.8 cm
So the length becomes 148.8 cm after it is increased by 24%.

Aand b are correctly balanced reactions. they have the same number of atoms in both sides of the reaction